Answer
St John's wort is contraindicated with efavirenz/emtricitabine/tenofovir disoproxil because it risks decreasing efavirenz plasma concentrations and reducing its clinical effects.
Sources for this answer
- Efavirenz/Emtricitabine/Tenofovir disoproxil Dr. Reddy's 600 mg/200 mg/245 mg Film-Coated TabletsDr. Reddy's Laboratories (UK) Ltd · emc · SmPC §4.3 Contraindications · Version 12Document updated
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